Michael Deacon watches the London Mayor's speech at the Conservative Party
Conference, in which he compares George Osborne to a dustpan and Michael
Gove to a jay-cloth.

Boris Johnson was coming. You could tell it was him because you couldn’t see him. Everywhere the Mayor of London goes at the Tory conference, he’s swarmed to the point of invisibility by cameramen and hacks, the ones at the front walking backwards, those to his side and rear jostling. It must save the Mayor a fortune in security costs. No wannabe assailant could hope to get near him.

Half an hour before the Mayor was due to give his speech, the swarm zig-zagged past the monstrous queue of delegates waiting to hear him. Reflexively, the queue chuckled. This has become the default response of the public to spotting Boris: people laugh even when he isn’t doing or saying anything funny. He’s like a political Tommy Cooper. Cooper had only to arrive onstage to set the crowd off: they were laughing in anticipation of laughing. And so it is with Boris. The audience is conquered before the act has begun.

Most politicians are grateful for a standing ovation when they walk off. Today Boris got a standing ovation for walking on. Why do delegates love him so much? Partly it’s because, with his vim and chivvying, he’s the only senior Tory who makes them feel optimistic, even cheerful, about their future.

But also I think it’s his bodily proportions. Outsize head, rounded face, rounded body, pudgy hands, vaguely unsteady on his feet – he looks, in outline, like a giant toddler. It’s eerily easy to picture him waving a rusk and spilling a Tommee Tippee beaker of juice down his tie. The love for Boris isn’t just political, it’s maternal.

I don’t know how much maternal love David Cameron feels for him but none the less the Prime Minister was present, eight rows from the front. Cameras were trained on Mr Cameron like guns. One false move – a resentful scowl, a roll of the eyes – and they would strike. But, under great pressure, he executed his reactions perfectly, throwing his head back with laughter whenever he was the butt of the joke (“I commend the tough decisions you have taken – not least to come along and hear this speech…”).

As hardly needs saying, the speech was funny. “David, you are a broom, a broom cleaning up the mess left by Labour! And your colleagues: George Osborne the dustpan, Michael Gove the jay-cloth, William Hague the sponge…”

The trouble with being funny, though, is that your audience will want you to be funny all the time. Whole minutes went by when the Mayor was being serious – about apprenticeships, schools, housing – and you could sense the audience wasn’t really paying attention; they were coughing, fidgeting, impatient for him to get off this politics stuff and on to the next gag.

Is it a problem, this reluctance to take him seriously? Maybe not. Maybe, in an age when politicians seem to have less and less power to control events, the job of Prime Minister is increasingly to act as a kind of national cheerleader and pick-me-up. If so, it’s hard to think of a more obvious candidate. As long as he doesn’t rest his Tommee Tippee beaker on the nuclear button.